Add test for complex break paths

Author: Noblix

tests/break-paths-complex.slang

@@ -0,0 +1,36 @@
+method client(n: Int)
+{
+    var i: Int := 30;
+    var j: Int := i;
+    loop
+        invariant i >= 15
+        invariant i <= 30
+        decreases i
+    {
+        i == 15 =>
+            match {
+                n % 2 == 0 =>
+                    j := -1;
+                    break,
+                n % 2 == 1 =>
+                    j := -2;
+                    break
+            };
+            i := i - 1,
+        true =>
+            i := i - 1
+    };
+
+    match {
+        n % 2 == 0 =>
+            assert j == -1,
+        n % 2 == 1 =>
+            // This fails because j is actually -2
+            // @CheckError
+            assert j == -3,
+    };
+
+    // this is reachable so should also fail
+    // @CheckError
+    assert false
+}